Created Bill Not saving and other problems

1. I create a bill and enter the price amount. The four digits entered but immediately disappear. I renter them and update the quantity field. The correct amount shows up in the Totals fields but then changes to a zero.

2. When I save the bill and go back to the Bills page t is not saved. 

Has anyone experienced this or I am doing something wrong?

Yes, after upgrading to 2.0.2 I'm experiencing this issue. I don't know even where to start troubleshooting this.

The same issue came back now for version 2.1.0
I can't insert the items in the bill anymore